JP2010019680A - Watthour meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a watthour meter detecting a rise in temperature, which is predicted to cause damage of the watthour meter. <P>SOLUTION: Temperature detecting sections 109, 110 are provided to portions in the vicinity of conductive sections 102, 103 or terminal sections 101A, 101B in the watthour meter. When a control section 114 determines that data relating to the temperature output from the temperature detecting sections 109, 110 is higher than a predetermined value, displaying or communication about information that the temperature is higher than a predetermined value, is performed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a watt-hour meter that measures the amount of power used by a system under measurement.

Conventionally, watt-hour meters that measure the amount of power used by ordinary households, factories, and offices have become widespread. The watt-hour meter displays a usage amount detecting means for measuring the used power amount of the system to be measured, a control portion for editing the usage amount detected by the usage amount detecting means into data, and data edited by the control portion. And a display unit. (For example, Patent Document 1)
JP 2004-226094 A (page 10, FIG. 2)

Generally, a watt-hour meter is composed of a power supply side distribution line that receives power from a power supply company and a terminal part to which a load side distribution line that supplies power to consumers is connected, and a terminal to which the power supply side distribution line is connected. The electroconductive part which conducts electric power between the terminals to which the load side distribution line is connected is provided. The power supply side distribution line and the load side distribution line are electrically connected by screwing or the like to the terminal part, but if the electrical connection is not good, the electrical resistance becomes high and the terminal part The temperature rises. Moreover, when the electric current exceeding the rated current of a watt-hour meter is used by a consumer, the temperature of the said terminal part and an electroconductive part rises. The temperature rise may damage not only the internal circuit of the watt-hour meter but also the electrical equipment and houses of the customer.

The conventional watt hour meter did not have temperature detecting means for detecting the temperature rise of the conductive part that conducts electric power to the terminal part or the load, so the temperature rise before the watt hour meter breaks due to the temperature rise. There was a problem that cannot be detected.

  An object of this invention is to provide the watt-hour meter which can detect the temperature rise estimated that it leads to the damage of a watt-hour meter in view of the said problem.

In order to achieve the above object, the watt-hour meter according to the present invention includes a first terminal part to which a power supply side distribution line is connected, a second terminal part to which a load side distribution line is connected, and the first terminal part. A conductive portion that electrically connects the terminal portion and the second terminal portion; a calculation portion that calculates data relating to power used by a consumer from a current value and a voltage value that appear in the conductive portion; and Output means for outputting data relating to the calculated power consumption of the consumer, temperature measuring means for measuring the temperature of at least one of the first terminal part, the second terminal part, and the conductive part, and the temperature A determination unit that determines whether the temperature measured by the measurement unit is equal to or higher than a preset setting value, and an alarm is output when the determination unit determines that the temperature is equal to or higher than a preset setting value. And a notification means To.

  ADVANTAGE OF THE INVENTION According to this invention, the watt-hour meter which can detect the temperature rise estimated to lead to the damage of a watt-hour meter can be provided.

  Examples of the present invention will be described below.

[Example 1]
Embodiment 1 of an electric energy meter according to the present invention will be described with reference to FIG. FIG. 1 is an internal configuration diagram showing a first embodiment of a watt-hour meter according to the present invention. This embodiment is shown for a single-phase two-wire watt-hour meter.
In FIG. 1, 100 is a watt-hour meter main body.

101A and 101B are terminal portions, and a conductive portion made of a conductive metal such as brass or copper is arranged in a fixed portion made of a highly insulating plastic material such as phenol resin or PBT resin. Thus, an external distribution line is connected to the watt hour meter main body 100. The 1S and 2S terminals of the terminal portion 101A are connected to a power supply side distribution line that receives power from the power supply company, and the 1L and 2L terminals of the terminal portion 101B are connected to a load side distribution line that supplies power into the consumer.

Reference numerals 102 and 103 denote conductive portions made of a conductive metal material such as copper. The conductive portion 102 is between 1S of the terminal portion 101A and 1L of the terminal portion 101B, and the conductive portion 103 is of the terminal portion 101A. Electrical connection is established between 2S and 2L of the terminal portion 101B.

A current detection unit 104 includes a shunt resistor, a hall element, or a current transformer, and is attached to the conductive unit 102 to detect a current (A1) between 1S of the terminal unit 101A and 1L of the terminal unit 101B. It is converted into a low-level voltage signal that is directly proportional to the current consumed by the customer and output.

A voltage detection unit 105 includes a voltage dividing resistor such as an attenuator, a voltage transformer, and the like. Is converted into a voltage signal and output.

Reference numeral 106 denotes an encoding unit composed of an analog-digital converter or the like, which converts an analog-to-digital conversion of a low level voltage signal directly proportional to the current (A1) between the terminals 1S-1L output from the current detection unit 104. For example, it is output as 16-bit digital data.

Reference numeral 107 denotes an encoding unit, which includes an analog-digital converter or the like, and converts a low-level voltage signal output from the voltage detection unit 105 directly in proportion to the voltage (V1) between the terminals 1S-2S from analog to digital. For example, it is output as 16-bit digital data.

Reference numeral 108 denotes a power calculation unit, which includes a digital multiplication circuit, a DSP (digital signal processor), and the like. The digital data relating to the current (A1) output from the encoding unit 106 and the encoding unit 107 output the digital data. The digital data related to the voltage (V1) is multiplied and converted into digital data (A1 · V1) that is directly proportional to the power used by the consumer.

Reference numerals 109 and 110 denote temperature detectors, each of which includes a resistance temperature detector. The temperature detector 109 is in the vicinity of the conductive portion 102, the terminal portion 101A1S terminal or the terminal portion 101B1L, and the temperature detection portion 110 is the conductive portion 103. It is attached in the vicinity of the terminal portion 101A2S terminal or the terminal portion 101B2L terminal, measures the temperature, and outputs it as temperature data.

An encoding unit 111 includes an analog-digital converter and the like. The temperature data output from the temperature detection units 109 and 110 are converted from analog to digital and output as, for example, 16-bit digital data.

Reference numeral 112 denotes an opening / closing unit that is configured by a switch such as a relay, and is provided in the conductive unit 103 to cut off power supply to a load-side distribution line that supplies power into the consumer.

A timer unit 113 includes a counting circuit having a crystal oscillation circuit, and counts time.

Reference numeral 114 denotes a control unit which is configured by a microcomputer or the like, and edits the calculation result of digital data (A1 · V1) output from the power calculation unit 108 that is directly proportional to the consumer's power consumption as usage data, and stores it. Control display, transmission. Here, the usage data refers to data relating to the power consumption of the consumer, such as the total cumulative power consumption of the system to be measured and the time zone usage for each time zone. In addition, the control unit 114 receives digital data related to the temperature of the temperature detection units 109 and 110 from the encoding unit 111, and controls storage, display, and transmission of the data related to the temperature. In addition, the control unit 114 performs opening / closing control of the opening / closing unit 112.

Reference numeral 115 denotes a storage unit which is composed of a semiconductor memory such as a RAM, and stores usage data, temperature data, and the like.

Reference numeral 116 denotes a liquid crystal display or the like, which displays usage data, temperature data, and the like under the control of the control unit 114.

Reference numeral 117 denotes a communication unit, which includes a radio wave transmission / reception circuit, an interface circuit such as a current loop, and the like, and performs communication with the outside under the control of the control unit 114.

Next, the operation of this embodiment will be described with reference to FIG.

The current detection unit 104 detects a current (A1) flowing through the conductive unit 102 connecting 1S of the terminal unit 101A and the 1L terminal of the terminal unit 101B, and converts the current (A1) into a low-level voltage signal that is directly proportional to the consumer's current. Output. The current detection unit 104 includes a shunt resistor, a current transformer, a Hall element, or the like, and always outputs a low-level voltage signal that is directly proportional to the current used by the consumer to the encoding unit 106.

The voltage detection unit 105 detects the voltage (V1) appearing between the 1S and 2S terminals of the terminal unit 101A, converts the voltage (V1) into a low level voltage signal that is directly proportional to the use voltage of the consumer, and outputs the voltage signal. The voltage detection unit 105 includes a voltage dividing resistor such as an attenuator, a voltage transformer, and the like, and always outputs a low-level voltage signal directly proportional to the use voltage of the consumer to the encoding unit 107. .

The encoding unit 106 performs analog-to-digital conversion on a low-level voltage signal that is directly proportional to the consumer use current (A1) output from the current detection unit 104, and outputs the signal as, for example, 16-bit digital data.

The encoding unit 107 performs analog-to-digital conversion on a low-level voltage signal that is directly proportional to the use voltage (V1) of the customer output from the voltage detection unit 105, and outputs it as, for example, 16-bit digital data.

The power calculation unit 108 is configured by a digital multiplication circuit, a DSP (digital signal processor), and the like, and the digital data related to the current (A1) output from the encoding unit 106 and the digital data output from the encoding unit 107. The digital data related to the voltage (V1) is multiplied and converted into digital data (A1 · V1) that is directly proportional to the power used by the consumer, and output to the control unit 114.

The temperature detection unit 109 constantly measures the temperature of the 1S terminal of the conductive unit 102 and the terminal unit 101A or the 1L terminal of the terminal unit 101B, and outputs the temperature data. The temperature detection unit 110 constantly measures the temperature of the conductive unit 103, the terminal unit 101A2S terminal, or the terminal unit 101B2L terminal, and outputs it as temperature data.

The encoding unit 111 performs analog-digital conversion on the temperature data output from the temperature detection units 109 and 110, and outputs the data as, for example, 16-bit digital data.

The control unit 114 is configured by a microcomputer or the like, and receives digital data (A1 · V1) that is directly proportional to the power consumption of the consumer output from the power calculation unit 108, and calculates usage data. Here, the usage data refers to data relating to the power consumption of the consumer, such as the total cumulative power usage of the customer and the time zone usage for each time zone. The control unit 114 stores the calculated usage data in the storage unit 115, displays it on the display unit 116, and transmits it to an external device (not shown in the figure) via the communication unit 117.

In addition, the control unit 114 receives the digital data from the encoding unit 111 and determines whether the temperature data output from the temperature detection units 109 and 110 is equal to or higher than a preset first temperature set value. . When it is determined that at least one temperature data output from the temperature detection units 109 and 110 is a first preset temperature value, for example, 80 degrees Celsius or higher, the control unit 114 determines that the temperature is the first temperature setting value. Is displayed on the display unit 116 and transmitted to an external device (not shown in the drawing) via the communication unit 117. Further, the control unit 114 stores the temperature data at the time point and the time when the temperature is generated in the storage unit 115, displays the temperature data on the display unit 116, and transmits the data to an external device (not shown in the drawing) via the communication unit 117.

Further, the control unit 114 receives the digital data from the encoding unit 111 and determines whether the temperature data output from the temperature detection units 109 and 110 is equal to or higher than a preset second temperature set value. . When it is determined that at least one temperature data output from the temperature detection units 109 and 110 is a preset second temperature set value, for example, 120 degrees Celsius or more, the control unit 114 causes the switch 112 to Control to open state and cut off power supply to load. Further, the control unit 114 causes the display unit 116 to display an alarm indicating that the temperature is equal to or higher than the second set temperature value, and transmits the alarm to an external device (not shown in the drawing) via the communication unit 117. The control unit 114 stores the fact that the switch 112 is in the open state, the temperature data at that time, and the time at which the temperature is generated in the storage unit 115 and also displays the data on the display unit 116 via the communication unit 117. Transmit to the device (not shown in the figure). Note that the operation of closing the switch 112 again is performed when the command for closing the switch 112 transmitted from an external device (not shown) is received via the communication unit 117. 114 is performed by controlling the switch 112 to be closed.

If the present embodiment is used, if the controller 114 determines that the temperatures of the conductive portions 102 and 103 and the terminal portions 101A and 101B of the watt hour meter main body 100 are equal to or higher than a certain value, the temperature is equal to or larger than a certain value. Since it is displayed on the display unit 116 and transmitted via the communication unit 117, the watt-hour meter is damaged by a consumer person or an administrator who recognizes that the temperature is equal to or higher than a certain value by the display or transmission. The cause of the abnormal temperature rise can be investigated in advance, and damage to the watt hour meter and damage to the electrical equipment and houses of the consumer can be prevented.

Further, if the control unit 114 determines that the temperatures of the conductive portions 102 and 103 and the terminal portions 101A and 101B of the watt hour meter main body 100 are equal to or higher than a certain value by using this embodiment, the control unit 114 switches the switch. Since 112 is controlled to be in the open state, the power supplied to the consumer is cut off, and the watt-hour meter can be prevented, and the consumer's electrical equipment and the house can be prevented from being damaged.

  As described above, by using the present invention, it is possible to provide a watt-hour meter capable of detecting a temperature rise that is predicted to lead to damage to the watt-hour meter before the watt-hour meter is broken.

The internal block diagram which shows the structure of Example 1 of the watt-hour meter by this invention

Explanation of symbols

100 watt-hour meter main body 101A, 101B terminal unit 102 conductive unit 103 conductive unit 104 current detection unit 105 voltage detection unit 106 encoding unit 107 encoding unit 108 power calculation unit 107 comparison unit 108 timer unit 109 temperature detection unit 110 temperature detection unit 111 Coding unit 112 Opening / closing unit 113 Timer unit 114 Control unit 115 Storage unit 116 Display unit 117 Communication unit

Claims (4)

A first terminal portion to which the power supply side distribution line is connected;
A second terminal to which the load-side distribution line is connected;
A conductive portion that electrically connects the first terminal portion and the second terminal portion;
A calculation unit that calculates data on the power used by consumers from the current value and voltage value appearing in the conductive unit, and
Output means for outputting data relating to the power consumption of the consumer calculated by the calculation unit;
Temperature measuring means for measuring the temperature of at least one of the first terminal part, the second terminal part, and the conductive part;
Determining means for determining whether the temperature measured by the temperature measuring means is equal to or higher than a preset value;
An watt-hour meter comprising: an informing means for outputting an alarm when the judging means judges that the temperature is equal to or higher than a preset value. The watt-hour meter according to claim 1, wherein the notification unit is a display unit. The watt-hour meter according to claim 1, wherein the notification unit is a communication unit. A first terminal portion to which the power supply side distribution line is connected;
A second terminal to which the load-side distribution line is connected;
A conductive portion that electrically connects the first terminal portion and the second terminal portion;
A calculation unit that calculates data on the power used by consumers from the current value and voltage value appearing in the conductive unit, and
Output means for outputting data relating to the power consumption of the consumer calculated by the calculation unit;
An opening / closing part for blocking electrical conduction of the conductive part;
Temperature measuring means for measuring the temperature of at least one of the first terminal part, the second terminal part, and the conductive part;
Determining means for determining whether the temperature measured by the temperature measuring means is equal to or higher than a preset value;
A watt-hour meter comprising: control means for controlling the open / close section to be opened when the judgment means judges that the temperature is equal to or higher than a preset value.

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